The present invention relates to a powder coating cabin, and in particular to a powder coating cabin of column-shaped design and of a type including a housing having a cabin ceiling and a cabin bottom, and a coating unit arranged on the housing for spraying powder onto an object.
In the field of powder coating, that need for a frequent change of paint is more and more demanded so that the cleaning of powder coating cabins becomes increasingly important. In this context, reference is made to commonly owned copending international patent application PCT/EP 95/04115, the disclosure of which is incorporated herein by reference, which discloses configurations of powder coating cabins which may have door-shaped gates for defining pre-coating and final coating sites and, possibly, have a closeable bore for passage of powder spray coating devices. Further disclosed in the above-referred international patent application are various embodiments of cleaning units for effecting a simplified purging of the interior space of the housing by use of compressed air and/or suction air and/or wet cleaning elements. The cleaning unit is movable in vertical direction, i.e. in vertical direction of the housing, to clean the inner wall surfaces of the housing when the housing is closed and forms a closed container. The cleaning unit is moved into the operative cleaning phase through the ceiling or laterally by opening the door-shaped gates for formation of the pre-coating and/or final coating sites. After closing the doors and the slots, the cleaning unit can be operated to carry out a cleaning of the inner wall surfaces of the housing. Practice has shown however that sufficient backup space must be provided laterally or above outside the housing for arrangement of the cleaning unit in the stand-by position so that the manner of loading and operating the powder coating cabin is restricted. In addition, there is also a risk of contamination of the cleaning unit in the stand-by position. In particular powder particles may remain on the cleaning unit, resulting in a risk of encountering undesired powder mixtures. Cleansing of the cleaning unit itself is relatively cumbersome and requires mostly manual labor.